a unit of geological time that is a subdivision of a period and is itself divided into ages

from 190 million to 135 million years ago; dinosaurs; conifers

In the geologic timescale, an age or stage in the Middle Jurassic, lasting between 164.7 ± 4.0 Ma (million years ago) and 161.2 ± 4.0 Ma.

a subdivision of the Middle Jurassic epoch that extends from about 175.6 to about 171.6 million years ago.

In the geologic timescale, the Bajocian is an age or stage in the Middle Jurassic.

In the geologic timescale the Bathonian is an age or stage of the Middle Jurassic; it lasted from approximately 168.3 to around 166.1 million years ago.

from 190 million to 135 million years ago; dinosaurs; conifers

In the geologic timescale, an age or stage in the Middle Jurassic, lasting between 164.7 ± 4.0 Ma (million years ago) and 161.2 ± 4.0 Ma.

a subdivision of the Middle Jurassic epoch that extends from about 175.6 to about 171.6 million years ago.

In the geologic timescale, the Bajocian is an age or stage in the Middle Jurassic.

In the geologic timescale the Bathonian is an age or stage of the Middle Jurassic; it lasted from approximately 168.3 to around 166.1 million years ago.